This invention relates in general to an apparatus for applying an improved adhesive to sheet insulation having drainage channels, and more particularly to an apparatus for applying an improved adhesive to a series of sheets of insulation having transversely spaced apart drainage channels while preventing the adhesive from entering the channels and thereby significantly reducing the amount of time and labor necessary for coating the sheets of insulation with adhesive, and further to an adhesive which includes means for defining channels through which moisture and/or air can pass.
Heretofore, it has been well known in the building and construction industries to attach sheets of insulation or insulation board to an erected building substrate such as gypsum, concrete, or other masonry. The sheets of insulation are applied uniformly to the entire substrate of the building for insulation purposes. An aesthetic, waterproof, and impact-resistant finishing material or system is generally applied over the insulation. One example of such an application is the xe2x80x9cTHOROWALLxe2x80x9d system in which the insulation is an Expanded Poly-Styrofoam, commonly referred to as xe2x80x9cEPS.xe2x80x9d xe2x80x9cTHOROWALLxe2x80x9d is a trademark owned by Thoro System Products. Besides EPS, there are numerous types of sheet insulation material including different types of styrofoam available for use in building construction. The EPS sheets are generally light in weight, approximately one pound per cubic foot, and their dimensions vary, although a standard size is two feet wide by four feet long with a thickness of one, two, or more inches. When affixed to a building substrate, the longer dimension of the sheets extends horizontally.
Although the finishing material is waterproof, moisture has a tendency to buildup between the insulation and substrate. To eliminate this moisture problem, the construction industry has developed and employed sheet insulation having spaced apart drainage channels along the shorter dimension of the sheets such that the channels are vertically disposed on and adjacent to the building substrate to funnel downwardly the moisture trapped between the substrate and the insulation. One example of the channeled sheet insulation is the xe2x80x9cINFINITYxe2x80x9d system in which the insulation includes beveled edges and vertically extending (i.e., when installed) drainage channels. xe2x80x9cINFINITYxe2x80x9d is a trademark owned by Dryvit Systems Inc.
While mechanical fasteners have been used to attach this type of sheet insulation to a substrate, a common method has been to apply adhesive or glue to the sheets of insulation to adhesively secure the insulation to an erected building substrate. Several types of adhesives are commercially available, some being more suitable to different substrates, different types of insulation, and differing climates. Also, it has been known to mix some adhesives with cement.
Heretofore, adhesives have either been manually applied to sheets of insulation or applied by adhesive-applying machines such as shown in U.S. Pat. No. 5,421,887. However, such machines are ineffective in applying adhesive to sheets of insulation having transversely spaced apart drainage channels because the machines would deposit adhesive into the drainage channels thereby blocking the drainage channels, which is undesirable. Moreover, even the manual application of conventional adhesives to sheets of insulation having drainage channels may result in the adhesive flowing into the channels when the insulation is pressed against the substrate, thereby blocking or closing the channels. Accordingly, there is a need for an adhesive which does not flow into the drainage channels when the insulation is pressed against the substrate and for an apparatus for applying the improved adhesive to a series of sheets of insulation having drainage channels and to additionally provide airflow passages between channels, while preventing the improved adhesive from entering the drainage channels.
The present invention overcomes the above problems in providing an apparatus for applying an improved adhesive to a series of sheets of insulation having transversely spaced apart drainage channels while preventing the adhesive from entering the channels and thereby significantly reducing the amount of time and labor necessary for coating the sheets with adhesive. Further, the improved adhesive of the present invention prevents or at least minimizes the amount of adhesive which flows into the drainage channels when the insulation is pressed against the substrate, thereby assuring the channels stay open to air flow. The improved adhesive compound includes a conventional adhesive containing a mixture of ground polyurethane spacer elements such as beads or particles. The beads act as spacers between the sheets of insulation and the substrate to limit the spreading of adhesive into the channels when the sheets are pressed against the substrate. Another embodiment of the invention is the use of the improved adhesive compound on standard sheets of insulation to define channels for moisture and/or air flow.
The adhesive applying apparatus of the present invention is an improvement to the adhesive applying apparatus disclosed in U.S. Pat. No. 5,421,887 which is incorporated herein by reference. The improved adhesive-applying apparatus includes a portable horizontally extending frame having an inlet section, an outlet section, and a central section disposed between the inlet and outlet sections. The inlet section of the frame includes a power-driven conveyor for driving a sheet of insulation from the inlet section to the central section and a magazine positioned above the conveyor for holding and dispensing sheets of insulation, one by one, onto the conveyor. The outlet section includes a sheet receiving conveyor having a stopping assembly for temporarily deactivating the power-driven conveyor until the sheet coated with adhesive is removed from the outlet section of the frame. The conveyor, the magazine, and the sheet receiving conveyor are all configured to hold, handle, and move the sheets of insulation along their shorter dimension, as opposed to holding, handling, and moving the sheets along their longer dimension as described in U.S. Pat. No. 5,421,887.
The sheets of insulation are coated with adhesive at the central section which includes an elongated or substantially wider adhesive dispensing hopper for storing and for applying the improved adhesive to the sheets of insulation as each sheet passes under the hopper. The hopper is adapted to dispense adhesive on the flat areas or portions of the sheets of insulation adjacent to the transversely spaced apart drainage channels. The bottom wall of the hopper includes a plurality of spaced apart slots aligned with these flat sections on the sheets of insulation through which the improved adhesive flows onto those sections. The hopper also includes a shutter for intermittently interrupting the flow of adhesive to the sheets of insulation to form substantially adhesive-free pathways on the sheets which provide communication between the drainage channels, thereby allowing the passage of air flow and/or moisture between drainage channels when the insulation is installed on the substrate. A screed is attached to the outlet wall of the hopper and includes a series of spaced apart teeth to form beads or lines of adhesive on the flat sections. The screed may further include a plurality of channel scraper blades to scrape away any adhesive that may enter the transversely spaced apart drainage channels.
To sequentially apply the improved adhesive to a series of sheets of insulation having transversely spaced apart drainage channels using the apparatus of the present invention, several sheets of insulation are loaded into the magazine arranged over the conveyer on the inlet section. The magazine dispenses the lowermost sheet onto the conveyor, and the conveyor drives the side edge of the sheet under the hopper. A pair of shutter driving wheels engage the sheet to facilitate the opening and closing of the shutter as the sheet moves under the hopper. The adhesive stored in the hopper flows through the spaced apart slots onto the flat sections of the sheet of insulation when the shutter is open and does not flow onto the sheet when the shutter is closed, thereby forming the substantially adhesive-free pathways between channels. The series of teeth along the lower end of the screed engage the sheet of insulation to uniformly spread the adhesive on the sheet. If channel scraper blades are included on the screed, and adhesive in the drainage channels will be removed as the sheet passes from underneath the hopper to the outlet section.
The apparatus may also be used to apply spaced apart beads of the improved adhesive on standard insulation sheets having substantially flat side walls to form channels between the beads that are maintained open when the sheets are applied to a building substrate.
As the sheet of insulation passes from under the hopper to the sheet receiving conveyor on the outlet section, it engages the stopping assembly which cuts power to the power-driven conveyer, thereby preventing the conveyer from driving the next sheet of insulation under the hopper until the first sheet coated with adhesive is removed from the outlet section. Once the first sheet is removed, the stopping assembly reactivates the power-driven conveyor which drives the second sheet of insulation completely under the hopper and to the outlet section. By repeating this process, adhesive is efficiently applied to sequential sheets of insulation.
It is therefore an object of the present invention to provide an apparatus for applying an improved adhesive to a series of sheets of insulation having transversely spaced apart drainage channels, wherein the channels will remain substantially open to air flow when mounted on a building substrate.
Another object of the present invention is to provide an apparatus for applying an improved adhesive to sheets of insulation having transversely spaced apart drainage channels which prevents adhesive from entering the channels.
Another object of the present invention is to provide an adhesive applying apparatus which forms substantially adhesive-free pathways across the sheets of insulation to allow communication between the drainage channels.
Another object of the present invention is to provide an improved adhesive compound adapted to be applied to sheets of insulation having one or more drainage channels which prevents the adhesive from flowing into the channels when the sheets of insulation are pressed against a substrate.
A still further object of the invention is to provide an improved adhesive-applying apparatus for applying an adhesive compound to sheets of insulation having drainage channels, which prevents adhesive from blocking or closing the channels when the sheets are affixed to a building substrate.
A further object of the invention is to provide an improved apparatus in combination with an improved adhesive for defining moisture and/or air flow channels on sheets of insulation secured to a building substrate.
Other objects, features and advantages of the invention will be apparent from the following detailed disclosure, taken in conjunction with the accompanying sheets of drawings, wherein like reference numerals refer to like parts.